But Gaudí was not the only creative genius with an enduring legacy who called Barcelona home. Pablo Picasso grew from a teenager into a young man while he lived in the port city, and a superb collection of works from his formative years is on display at the Museu Picasso.

With an artist in the family (my wife), the museum was decreed a must-visit far in advance. Savvy enough not to object, my daughters simply bow to the inevitable and accept that they will get an excellent education in one of the 20th century’s most famous painters. Plus, um, a little extra.

La Sagrada Família, scheduled to be completed in 2026, 144 years after its construction began, relies mostly on donations to keep the work going.

Manfred Gottschalk/Lonely Planet Images

More than 3,800 paintings, drawings, ceramics and sculptures are in the museum’s collection, housed in five adjoining buildings. We arrive on a cloudy day, happy to see that predictions of a tourist traffic jam are unfounded. The museum divides its collections into 16 rooms, separating them by category, ranging from his works as a boy wonder through the Blue Period and Rose Period to, finally, Ceramics.

Picasso’s teenage artworks are earnestly realistic and bear no hint of the Cubism style that would mark his pieces so indelibly in later years. And to the horror of my wife, there is plenty of realism in a particularly erotic drawing that she sees a split second after the girls stop in front of it. I can’t be sure which is louder: the sound of my daughters’ jaws hitting the floor when they happen across such a non–G-rated item in a public space or my wife’s gasp a few embarrassed heartbeats later.

The shock quickly subsides — we’re in Europe, after all. But, like almost every moment of our visit to Barcelona, it’s unforgettable. And how do you put a price tag on that?